High
Lock out radiator light on Chaffoteaux Sterling FF

Your boiler has failed to light the gas flame and has safely shut itself down to prevent any risk.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

Technical description

If the main burner is not established after 5 seconds then the boiter tbils safe to lockout and has to be reset manuaEbyy operating the main ON / OFF switch.

Engineer required

This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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